As of May 2021, Mango does not support transformation of datasets using the new Australian geodetic datum "GDA2020".
All data uploaded to Mango is transformed to EPSG:3857 WGS84 Pseudo Mercator, or 'web Mercator' (here's why we do this). To perform these transformations, we rely on ICSM and other official bodies to provide the transformation specifications.
The official parameters and transformation support files released by the ICSM can only be used when transforming between GDA94 geographic coordinates and GDA2020 geographic coordinates, or vice versa.
Without accurate transformation data, we cannot accurately process transformations of your data to Web Mercator.
We are continuing to investigating the best processes to ensure any transformations that we apply are accurate, and where this development will fit in the product roadmap.
Uploading GDA2020 data as GDA94
Shapefiles using GDA2020 can be uploaded using a GDA94 PRJ. The shift of datasets uploaded in this way will be around 1.8m.
For display purposes at the scale ranges available in Mango, this shift often isn't problematic.
A GDA94 PRJ, via epsg.io
GEOGCS["GDA94",DATUM["D_GDA_1994",SPHEROID["GRS_1980",6378137,298.257222101]],PRIMEM["Greenwich",0],UNIT["Degree",0.017453292519943295]]